The Working Time Regulations 1998 set the limits on how long and how often people in the UK can work. Most employers know the headline — the 48-hour week — but fewer are confident about the part that actually gets tested in a dispute or an HMRC check: the records you are expected to keep to prove you stayed within the rules. This is a plain-English run through what those records are.
The 48-hour week is an average, not a ceiling
A worker should not work more than 48 hours a week on average. The key word is average. It is measured over a reference period — normally 17 weeks — so a 55-hour week is not a breach on its own, provided quieter weeks bring the average back down.
Workers can choose to opt out of the 48-hour limit, but the opt-out must be in writing, it is voluntary, and a worker can cancel it with notice. You cannot make signing it a condition of the job. If you rely on opt-outs, the signed agreements are part of your records — keep them.
Rest breaks and rest periods
Alongside the weekly limit, adult workers are entitled to set rest. The figures worth committing to memory:
- A 20-minute rest break when the working day is longer than 6 hours.
- 11 hours' rest between working days.
- 24 hours off in each 7-day period, or 48 hours in each fortnight.
You are not generally required to log the exact minute of every tea break, but you should be able to show that your working patterns allow the required rest — and where breaks affect pay, a clear record of break start and end times removes the argument before it starts.
Night work has its own duties
Night workers — broadly, those who regularly work at least three hours during the night period — should not work more than 8 hours on average in each 24-hour period. On top of the hours record, you must offer a free health assessment before someone starts night work and at regular intervals after. Keep evidence that the assessment was offered.
So what records do you actually need?
There is no single prescribed form, but to demonstrate compliance you should be able to produce the following for any worker, going back far enough to cover the reference period:
| Requirement | What to keep |
|---|---|
| 48-hour week | Hours worked per worker across each 17-week reference period. |
| Opt-out | The signed, dated opt-out agreement, plus an up-to-date list of who has opted out. |
| Night work | Night hours per worker, and records that a health assessment was offered. |
| Rest & breaks | Working patterns and, where breaks affect pay, break start and end times. |
As a practical retention rule, keeping these for at least two years covers the reference period comfortably and lines up with how long disputes tend to surface. Plenty of employers keep them longer alongside payroll records.
Hours, breaks and the 48-hour limit, captured as you go
TempClock records verified hours and break times on every shift, tracks each worker's average against the 48-hour week, and exports payroll-ready timesheets to Sage 50 and Xero — so the Working Time record is a by-product of paying people, not a separate chore.
Why this gets hard for agencies
For a single employer with a fixed team, the 17-week view is manageable. For an agency placing temps across many clients, the same worker's hours are spread across sites and weeks, which is exactly where a paper or spreadsheet system loses the thread. If you cannot pull one worker's full hours across the reference period in a few clicks, you do not really have the record the Regulations expect — you have the raw materials for it.
The fix is the same one that fixes payroll accuracy: capture verified hours at the point of work, attribute them to the worker rather than the site, and keep them somewhere they can be totalled and exported. Get that right and Working Time compliance stops being an annual scramble and becomes something you can prove on demand.